It is known that an organic polymer having at least one reactive silicon group in the molecule undergoes crosslinking by formation of siloxane bonds accompanying a hydrolysis reaction or the like of the reactive silicon group with moisture or the like even at room temperature, and a rubber-like cured article can be obtained.
Among the polymers having a reactive silicon group, organic polymers in which the main chain skeleton is a polyoxyalkylene polymer and/or a (meth)acrylate polymer are disclosed in (Patent Document 1), (Patent Document 2) and the like. Those polymers have already been industrially produced, and are widely used in applications to sealants, adhesives, coatings and the like.
Curable compositions comprising the above described organic polymers having a reactive silicon group are cured by using silanol condensation catalysts, and usually organotin catalysts having a carbon-tin bond such as dibutyltin bis(acetylacetonate) are widely used. However, in recent years, toxicity of organotin catalysts is pointed out, and development of non-organotin catalysts are demanded.
Dealcoholization type silicone compositions using organic titanates as a non-organotin catalyst are available on the market, and are widely used in a variety of applications. This technique is disclosed in (Patent Document 3), (Patent Document 4) and the like.
However there are relatively few examples of adding an organic titanates to organic polymers containing a reactive silicon group. Those examples are disclosed in (Patent Document 5), (Patent Document 6), (Patent Document 7), (Patent Document 8), (Patent Document 9), (Patent Document 10), (Patent Document 11), (Patent Document 12), (Patent Document 13) and (Patent Document 14).
On the other hand, as disclosed in (Patent Document 15), (Patent Document 16), (Patent Document 17), (Patent Document 18), (Patent Document 19), (Patent Document 20), (Patent Document 21), (Patent Document 22), (Patent Document 23), (Patent Document 24) and the like, sometimes to organic polymers containing a reactive silicon group are added various photostabilizers for the purpose of improving weather resistance.    Patent Document 1: JP-52-73998A    Patent Document 2: JP-59-74149A    Patent Document 3: JP-39-27643B (U.S. Pat. No. 3,175,993)    Patent Document 4: U.S. Pat. No. 3,334,067    Patent Document 5: JP-58-17154A (JP-3-57943B)    Patent Document 6: JP-62-146959A (JP-5-45635B)    Patent Document 7: JP-5-311063A    Patent Document 8: JP-2001-302929A    Patent Document 9: JP-2001-302930A    Patent Document 10: JP-2001-302931A    Patent Document 11: JP-2001-302934A    Patent Document 12: JP-2001-348528A    Patent Document 13: JP-2002-249672A    Patent Document 14: JP-2003-165916A    Patent Document 15: JP-2001-19842A    Patent Document 16: JP-61-233043A    Patent Document 17: JP-5-287186A    Patent Document 18: JP-5-70531A    Patent Document 19: JP-9-194731A    Patent Document 20: JP-2002-129004A    Patent Document 21: JP-11-172110A    Patent Document 22: JP-11-21442A    Patent Document 23: JP-2000-273439A    Patent Document 24: JP-2001-271057A